Culturing cells for the commercial production of therapeutic proteins is a costly process. The equipment required is expensive and research and development and production costs are high. Development of cell culture processes which maximize the quantity of therapeutic protein produced per liter of cell culture will minimize the resources necessary to produce a given quantity of the protein. It is, thus, desirable to use commercially viable reagents which produce large quantities of proteins.
Many naturally occurring cells do not produce large quantities of desired proteins, under standard culture conditions. Rather, extensive research and development of cell culture processes, which coax cells in culture to generate large quantities of therapeutic protein, must be performed. Typically, identifying plasmid vectors useful for expressing a protein at a high level requires a significant amount of inventive input.